In a constantly changing market, it is important to get your product out on the market as soon as possible. This is especially important for mobile phones since their life cycle is short. Products have drastically reduced their time to get on the market during the last few years. Nowadays the components are mainly developed through experience than testing and investigation. However, a number of tests are used today to test mobile phones. These test specifications are called GREAT, Global, Reliability and Environmental Test Specification and contain climate tests (high and low temperature, humidity, solar radiation etc), durability tests (repeated operation, fatigue), electrical tests (ESD, excessive voltage etc), functional tests (inspections, performance check, acoustical checks), mechanical tests (free fall, vibration, bend, pressure etc) and reliability tests (accelerated ageing). All these test are made on complete assembled phones and this is both time demanding and costly.
To develop a mobile phone it often requires a number of prototypes, generally four, before the phone is launched. Each prototype is GREAT tested and if one component is not durable enough, some changes have to be made and then the new component has to wait for the next prototype to be tested again. This may sometimes result in that it requires even more than four prototypes before the phone can be launched. A previous component impact tester comprising a pendulum was previously tested. The main problem with the pendulum was that it was a very large and ungainly design, about 2 meters high. Because of its size, it was not practical and not safe enough for the user. Another fundamental disadvantage was that the pendulum did not reach enough velocity when it hit the component.
Today a Free Fall test is a part of GREAT, which is used on mobile phones today. The purpose with the Free Fall test is to simulate the end user dropping the phone accidentally during intended use or during transport. There are three drop scenarios, face and/or edge and/or corner drops. All the drops are performed from 1.5 meters on a complete assembled mobile phone on concrete. The phone is powered on during the whole test. Nine tests are performed twice on each test phone and in total there are fifty-four tests made on 3 phones. The phone is inspected for damage and basic functionality after each test. All damages including cosmetic failure are reported by a template.
There is a need to find a precise testing of light moulded plastic parts before the mobile phone is completed in order to verify or control the strength of the plastic part.
There is further a need to find a test method that can point out variation in material quality in an earlier stage than the Free Fall test. Thereby, the material testing of the components can be moved out from the mobile manufacturer to the plastic component suppliers.